A new voice-data integrated protocol for unidirectional broadcast bus networks

The authors extend the p_i-persistent protocol previously proposed to include voice for multiaccess communication over unidirectional broadcast bus networks. They use a framed approach for integrating these two traffic types. Further, they use not only speech detectors for modeling speech sources, but also a movable-boundary scheme for their protocol in which the voice subframe size is estimated from the number of voice packets transmitted in the previous frame. The authors determine the fraction of speech loss and the fraction of wasted allocated bandwidth due to the estimator by formulating a Markov chain for the number of ready voice stations at the frame boundaries. To analyze data performance, a nonhomogeneous Markov chain is constructed for a data station´s buffer content just before the data slots visit that station. Then, these models are converted to homogeneous chains from which the authors determine the optimum p_i for each data slot